[R-SIG-Mac] Problem viewing overview pdf's

[Zak]

Just installed the latest (3.8.1) R for Mac OS X after working for a
year on a much older version. Now, when I use the package manager and
then select a package with an overview that happens to be a pdf then
the pdf does not open up in the lower pane as it used to but only a
black pane appears. The pdf's are definitely there (as I can access
them through the vignette() utility (Bioconductor). Is this a known
bug/feature? Is it something to do with installing over prior
versions? Help!

Thanks,

-Zak